Electric-socket plug



Oqt. 29, 1929. J. L.-L. HALL ELECTRIC SOCKET PLUG Filed May 26, 1926 II VVENTOk. dorm L.. L. HALL @(m/mm/ A TTORNEY Patented 0st. 29, 1929 star seine JOHN L. L. HALL, OF SAN DIEGO, CALIFORNIA ELECTRIC-SOCKET PLUG Application filed May 26,

My invention relates to electric socket plugs for easily, quickly and securely connecting electric fixtures and the like to the electric outlet or socket.

The objects of iny invention are: first, to provide an electric socket plug which may be easily inserted into an electric socket and substantially locked therein so that the same cannot be readily removed from the socket by pulling on the electric cord connected to the plug; second, to provide a plug of this class which may be quickly inserted into a conventional electric screw socketand easily secured therein without being rotated at all or to any I great extent; third, to provide a plug of this class in which the plug portion adapted to be inserted into a socket is smaller than the socket itself, thereby permitting the plug to be readily inserted into the socket and expanded when in place by positive means, preventing ready contraction of the plug portion, said plug portion after being expanded being adapted to be tightly screwed into the socket; fourth, to provide novel means in connection with a plug of this class for lock-' ing the plug portion thereof in expanded relation by means on a locking member, which means is adapted to engage a retaining por tion on the expanding member of the plug; fifth, to provide as a whole a novelly constructed electric device for readily and securely connecting electric apparatus to a source of electrical energy; sixth, to provide a socket plug in which the electric cable is directly connected to the contact supporting core so that any force applied on the cable is not transmitted to the enclosing casing of the core, and seventh, to provide a plug of this class which is particularly simpleand economical of construction, durable, eflieient, fool-proof,

and which will not readily deteriorate or get out of order.

lVith these and other objects in view, as will appear hereinafter,my invention consists of certain novel features of construction, com bination and arrangement of parts and portions, as will be hereinafter described in detail and particularly set forth in the appended claims, reference being had to the accompanying drawings and to the characters of refer- 1926. Serial No. 111,729.

ence thereon, which form a part of this appli cation, in which:

Figure l is a longitudinal side view of my socket plug in one form of construction; Fig.

2 is an end view thereof; Fig. 3 isa longitudinal sectional view thereof, taken through 33 of Fig 2, showing certain partsand 'portions in elevation to facilitate the illustration; Fig. l is a transverse sectional view thereof, taken through 4% of Fig. 3; Fig. 60, 5 is a side view of my socket plug with the outer casing removed, and Fig. 6 is a fragmentary side view of the'no'rinallyrear end of the plug with the outer casing removed,

Like characters of reference refer to similar 65, parts and portions throughout thev several views of the drawings.

The outer casing 1 of my socket plug is similar in construction and appearance as other plugs and sockets now on the market, except that thereis provided in one side and near its plug end a longitudinal slot 1 through which the fingerhold or knob of the locking member extends, as will be described hereafter. I Within the casing 1 is positioned the core 7 or contact insulating and supporting member 2, which is preferably made of fiber or other similar insulating material, said core extending beyond the forward or open end of the casing. Said core is provided intermediate so its ends with an annular flange 2, which is p0- sitionedagainst the forward or open end of the casing, the latter being secured in such position relative to the former by any suitable means, such as a screw 3, shown in Fig. 1. The portion of the core 2 positioned outside of and beyond the flange 2 is considerably reduced, as indicated by 2 in Figs. 2 and 3. At the one side of the reduced portion 2 is secured a sub-" stantially semicircularly shaped thread sec; 90. tion 4, which is preferably molded integrally with the reduced portion 2 and forms an externally threaded portion'over approximately one-half of the outer side of said reduced por- 7 tion, the pitch of which threaded portion conforms with the internally threaded portion of i a conventional screw socket of electric outlets. The diameter of the threaded section or inem ber l is slightly smaller than the inside diameter of the conventional electrical socket so that the reduced or plug portionof my device may be easilyinserted into the socket rwithout screwing the same therein.

At the side of the core opposite the side at which the semi-circular thread member 4 is secured, is a longitudinally slotted portion 2 which extends from the inner end ofthe core to the forward side of the annular flange,

the slotted portion extending preferably under the flange, as shown in Fig. 3. Vithin this slotted portion 2 is positioned a resilient spring contact member 5 made preferably of sheet metal and consisting of a pressed,

. threaded section or segment 5*, positioned at the opposite side of the reduced portion 2 from the member 4, and a longitudinally slotted resilient shank portion 5*, the shank being positioned in the slotted portion 2 and secured to near the inner end of the core 2 by means of a bolt 6 extending transversely through the rear endof the core and into a large cut-away portion or recess 2 intermediate the rear end of the core and the flange portion 2 and'at'the side thereof opposite the slotted portion 2. To the end of the bolt 6 extending into the recess 2 is secured the one terminal of the electric cable 7. Be-

tweenthe cut-away portion 2 and the rearv end of'the core or contact supporting member is a wall portion 2", which is provided with an opening 2 through which the cable 7 extends. The portion of the cable? extending through the hole 2 is provided with a knot 7 which engages the inner side of the Wall portion 2 within the cutaway portion or recess 2 to prevent the cable from being withdrawn. Any force applied on the cable 7 is imparted directly on the core and not'on the outer casing 1,.as is the case in conventional electric plug and socket construction. The rear end'of the core 2 is provided with a backwardly extending reduced portion or boss 2 through which the hole 2 extends. This boss extends outwardly through an opening 1 in the rear end of the casing 1, as shown best in 'Fig. 3and insulates the cable from the casing.

In the slotted portion of the core 2 is reciprocally mounted a slide or look memberS, which is relatively narrow. at its upper portion but providedat its lower portion with oppositely disposed, outwardly extending flanges 8 which are positioned inthe space between the'bottom of the slotted portion 2? and the shank portion of the contact member'5, as shown in Fig. The member 8'is preferably yieldably held in position by the shank ofthe contact member 5.

ward end of the'lock member 8 is provided with an outwardly extending lug 8 beveled at its forward and rear sides and conforming substantially with the corrugations formed at the inner or under side of the contact portion 5 by forming the threads therein. The lug 8 is normally held in an inwardly shifted or The for.

receded position, as indicated by dotted lines in Fig. 3, when the plug is not in use or when inserting and removing the plug into and from a socket, the receded position of the lug permitting the threaded portion of the memher 5 to be contracted relative to the threaded member 4 by the spring action of the contact member. When the lug 8 is shifted outwardly, the threaded contact portion 5" is expanded relative tothe threaded member 4 and substantially locks the plug in position in the socket, the corrugations at the inner side of the threaded portion 5? retaining the lug 8 when shifted outwardly to certain positions. The side of the reduced portion 2 of the core at which the threaded portion of the contact member 5 is positioned isslightly inclined outwardly, as indicated by 2 in Fig. 3, to permit the outer end of the lock member 8 and of the contact member 5 to be shifted radially relative to the threaded portion or section 4 of the core when the lock member is shifted outwardly or forwardly. With this construction the plug. portion may be made to fit, and also locked relative to, sockets of slightly different diameters. At the inner or rear end of the reciprocating or look memberis provided a fingerhold or knob portion 8, which extends outwardlyrthrough the longitudinal slot 5 in the shank 5 ofthe resilient contact member 5 and outwardly through the longitudinal. slot 1 of the casing, as previously described, for readily manipulating the lock member and for shifting the lug 8 'at the forward end thereof. At the outer end of the reducedportion of the core is a sleeve 9, which may be pressed orotherwise secured therein. To one side of the sleeve 9 is a small hole 2 which connects the outer or forward end of the core with the recess 2. Through this hole 2 extends the other terminal of the cable 7, which terniinal is secured at its outer end to the sleeve ice I I claim as new and desire to secure by Letters Patent is:

1. In asocket plug, a contact member sup-, port having a plug portion at one end and. a

segmental threaded portion at one side of said plug portion, an elongated'contact' member secured at itsone end near the other end of said support, said contact member having a retaining and contact portion at its free end adapted to be resiliently held in contracted relation with the threaded portion at one side of the plug portion of said support, and a lock member longitudinally reciprocally mounted on said support and operable from the side thereof adapted to engage at its one end the inner side of the retaining and contact portion of said retaining and contact member for expanding the same relative to the threaded portion of said support.

2. In a socket plug of the class described, an insulating contact member support provided at one side of one end with a segmental threaded portion, a resilient contact member secured at its one end to the opposite side and near the opposite end of said support, said contact member being provided at its free end with a segmental threaded portion in opposed relation to the segmental threaded portion of said support and adapted to be held in contracted relation with the latter, and a lock member longitudinally reciprocally mounted at and operable from one side of said support contiguous to said contact member and adapted when shifted in one direction to engage the inner side of the segmental threaded contact portion of said contact member and shift said portion outwardly relative to said support.

3. In a socket plug of the class described,

an insulating contact member support provided at one side of one end with a segmental threaded portion, a resilient contact member secured at its one end to the opposite side'and near the opposite end of said support and provided at its free end with a pressed, segmental, threaded contact portion, said contact portion having corrugations at its inner side conforming with the threads at its outer side, and a lock member longitudinally reciprocally mounted on said support contiguous to said contact member and operable from the side of said support,'said lock memher having a lug at its one end, adapted when shifted outwardly to engage the corrugations at the inner side of said contact member for positively holding the contact portion of said contact member in expanded relation with the segmental threaded portion of said support.

4:. In a socket plug of the class described, an insulating core having a reduced portion at its end one and a segmental threaded portion at one side of said reduced portion and a longitudinally slotted portion atv the opposite side thereof, a resilient contact member having a shank portion positioned in said slotted portion and secured at its one end to said core and provided at its opposite end with a pressed contact portion positioned at the side of said core opposite the threaded portion thereof, said contact portion of said contact member having conforming corrugations at its outer and inner sides forming at ber and provided at its opposite end with a beveled lug adapted to engage the corrugations at the inner'side of the contact portion of said contact member for forcing the same in expanded relation with the segmental threaded portion of said core, said corruga-v tions being adapted to hold said lock member in a lockingposition when the reduced portion of said core is inserted in an electric socket.

- -5, In a socketplug of the class described, an msulating core having a reduced portion at its one end and a segmental threaded portion atone-side of said reduced portion and alongitudinally slotted portion at-the opposite side thereof, a resilient contact member having a shank portion positioned in said slotted portion and secured at its one end to said core and provided at its opposite end w1th a pressed contact portion positioned at the side of said core opposite the threaded portion thereof, said contact portion of said contact member havlng conforming'corrugations at its outer and inner sides forming at ber and provided at its opposite end witha beveled lug-adapted to engage the corrugatlonsat the inner side of the contact portion of said contact member for forcing the same in expanded relation with the segmental threaded portion of said core, said corrugations being adapted to hold said lock member in a locking position when the reduced portion of said core is inserted in an electric socket, a casing positioned over the outer side of said core andibackwardly from the reduced. portion thereof,-said casing being provided with a longitudinal slot in one side through which the knob of said lock member extends, and another contact member positioned at the end of the reduced portion of said core and electrically connected with the rear portion thereof.

6. In a socket plug, an insulating contact member supporting core having a large recess intermediate its ends and at one side thereof, a contact member mounted at one end of said core, another contact member resiliently supported at the side of said core opposite.

members, said cable having an enlarged re taining portion near its end, said enlarged retaining portion being positioned. within saidlrecess and against the wall forming the rear, side thereof, preventing ready Withdrawal of said cable from said recess.

'7. In a socket plug of the class described, an insulating contact member supporting core having a large recess intermediate its ends andat one side thereof and another recess extending longitudinally withsaid core at the side opposite said first mentioned recess, a contact member resiliently supported in said last mentioned recess and extending toward the one end of said core, another contact member secured at said end of said core and spaced from said first mentioned contact member, and a cable extending throughthe wall forming the rearside' of said first mentioned recess and into said recess, one terminal of said cable being connected with the contact member at the side ofisaid core and the other terminal extending through the for- Ward end of said core and connected with the contact member at the forward end thereof, said cable having a knot near its end within said firstmentionedrecess, said knot being positioned against the wall forming the rear side of said first mentioned recess preventing ready withdrawal of said cable therefrom.

8.In' a socketplug, an insulating contact member supporting core having a large recess intermediateits ends on one side 7 thereof, a contact member positioned on one sideof said core and connected to a terminal positioned within the recess, a further contact member secured at one end of said core, acable extending through a bossed portion at the other endrof said core andconnected with said last named contact and terminal, said cable I having an enlarged retaining portion positioned within said recess and against the rear wall thereof preventing ready Withdrawal of said cable therefrom, and a casing positioned around the recess and over the bossed portion of said core.

In testimony whereof, I have hereunto set my hand at San Diego, California, this 20th day of May, 1926. V p p 7 JOHN L) L. HALL. 

